The claimed invention pertains to the electric power industry. In particular, it improves the design of gas-discharge reflector lamps for general and special lighting.
A gas-discharge reflector lamp comprising a burner installed in a bulb with a reflective layer on its inside surface is known (USSR certificate of authorship No. 1069032, 01.23.84).
The shortcoming of the technical solution is the loss of lamp light flux as a result of a portion of rays reflecting off the reflective layer of an elongated burner, i.e., incident light rays. Elongated burners are the usual burner in mercury-vapor, metal-halide and sodium-vapor lamps. The problem is the inability to obtain various light intensity curves in longitudinal and lateral planes, which substantially reduces the lamp's performance.
The closest invention to solving this problem in the technical field is a gas-discharge reflector lamp, comprising a burner installed on current leads into the bulb, with at least one-half of the bulb's inside surface covered with a reflective layer so that the plane passing through the layer's longitudinal edges is parallel to the burner longitudinal axis (USSR certificate of authorship No. 1636896 Al, 03.23.91).
This technical solution, used as the prototype, makes it possible to obtain lamps with high light output and different light intensity curves in longitudinal and lateral planes, which is important when using the lamps for illumination of roads, greenhouses, etc.
The prototype's shortcomings results in the high cost of lamps due to the complexity of manufacturing axially asymmetric bulbs, or bulbs with uneven wall thickness, because it is impossible to rotate forms for injection when making the bulbs, and because of the high probability of tension in the glass during the lamp's operation.
The invention's objective is to reduce the cost of, and improve the quality of, gas-discharge reflector lamps. The stated objective is achieved when, in the case of a gas-discharge reflector lamp comprising a burner installed on current leads into the bulb, with at least one-half of the bulb's inside surface covered with a reflective layer so that the plane passing through the layer longitudinal edges is parallel to the burner longitudinal axis, the bulb has an ellipsoidal shape. In the area bound by the bulb neck and dome, the reflective layer's lateral edges are located in cross-sections where the bulb neck and dome join the ellipsoidal portion. The plane passing through the reflective layer's longitudinal edges is shifted from the bulb axis by a distance H and is located within 0.04-0.11 of maximum inside diameter D of the bulb. The burner is located in the longitudinal symmetry plane. In the cross-section passing through the bulb ellipsoid center, the ratio of the distance from the burner axis to the nearest surface of reflective layer 1 to the distance from the burner axis to the reflective layer edge L located in the longitudinal section is between 0.56 and 0.68. At least one current lead is located between the burner and the reflective layer in the longitudinal symmetry axis.